POPSUGAR - Gina Florio
Eric Leija, senior kettlebell trainer at Onnit who's also known as primal.swoledier on Instagram, and Jay Maryniak, NASM-CPT, CES, have teamed up to bless the world with their abs and full-body dumbbell workout. You might take one look at these guys and think, "There's no way I can keep up with …